We have deposited AlN thin films, which are highly thermally conductive insulating films, at room temperature independent of substrate and ambient temperature. We also evaluated the practicality of the obtained AlN thin film by measuring its thermal conductivity in the thermoelectric material Bi₂Te₃ using the 3ω method. AlN thin films were deposited on Bi₂Te₃ thin films, Ni thin plates and Cu thin plates using pressure gradient sputtering. As a result, an optimum insulating film with a thickness of about 800 nm was obtained after 2 h of deposition at a distance of 10 cm between the target and the sample. The thermal conductivity of Bi₂Te₃ was obtained to be 0.56±0.05 W/(m･K) by using the AlN thin film in the thermal conductivity measurement by the 3ω method. The thermal conductivity of Bi₂Te₃ measured using polyimide, which was conventionally used in the 3ω method, was 0.52±0.25 W/(m･K), which means that the measurement error was successfully reduced significantly. The above results indicate that this film is useful as a highly thermally conductive insulating thin film.

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This paper focuses on the improvement methods of leaf physiological impediments caused by caffeine. According to previous research, water extract from coffee grounds can promote the growth of Japanese mustard. Nevertheless, some other physiological impediments occurred in the leaves, which are caused by caffeine. The objective of this study concentrated on ameliorating the physiological impediments of leaves. The effects of caffeinated yeast fermentation broth on the growth and leaf status of Japanese mustard were systematically investigated. The results demonstrated that yeast fermentation could reduce the content of caffeine. Yeast fermented caffeine solution promoted the growth of Japanese mustard. In addition, caffeine fermented by yeast could significantly improve physiological disorders such as leaf etiolation and chlorosis. The reason of this phenomenon is the breakdown of caffeine by yeast, as well as the fertilizer effects of yeast itself. Therefore, the method may help ameliorate the caffeine-induced physiological impediments of Japanese mustard.

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As the hydrogen society progresses, Fuel Cell Vehicles (FCVs) are rapidly becoming more widespread. Metal hydrogen permeable membranes, which are the essential parts of the hydrogen fuels for polymer electrolyte fuel cells (PEFCs), require an alternative material to palladium from a cost point of view. Austenitic stainless steel, which is low cost, corrosion resistant, and easy to prepare for manufacture, has been considered unsuitable as a hydrogen permeable membrane because its passive film inhibits hydrogen permeation. However, destabilization of the surface oxide film and thin processing can be expected to improve its permeability. In this work, 18mass%Cr-8mass%Ni-2mass%Mo-Low Carbon (0.02mass%) stainless steel alloy (SUS316L) foils were irradiated with electron beam (EB) in a nitrogen atmosphere to investigate the effect of EB treatment on hydrogen permeability. The diffusion coefficient of hydrogen in the passive layer on the surface of stainless steel irradiated at 250 kV and 600 kGy was calculated to be promoted about 8 times compared to the untreated one, by applying Schmitz's multilayer hydrogen diffusion permeation model. Based on the results obtained, partial destabilization of the surface oxide film by irradiation treatment is suggested.

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The modern railway industry has been adopting aluminum alloy vehicle structures for their superior specific strength. The welding is often used in the assembly process of railway vehicle structures. The welding is an important technology in industry, as it is a joining method used not only in the railway, but also in the automotive, ship and other industries. In this study, the effect of welding on material properties was investigated. Aluminum alloy A7204, which is commonly used for railway vehicle body structures, was welded, and the welded specimens were evaluated from external observations and internal observations using an X-ray/CT system. As a result, the results of defect analysis by the X-ray/CT system differed depending on the humidity environment in which the weld specimens were fabricated. Specimens with higher humidity during welding tended to have an increased number and size of blowholes, which may lead to strength loss.

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During the ongoing COVID-19 pandemic, remote learning and conferencing have become increasingly common. However, these modalities are often facilitated through digital devices, resulting in a lack of immersion and difficulties in sustaining focus. This study explores how to enhance the sense of presence in remote lectures through the use of the Metaverse, a concept that has gained worldwide recognition. This report outlines the basic design and conceptual framework of the system.

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Carbon fiber reinforced epoxy plastics (CFRP) is widely utilized for light weighted aerospace structural materials. However, CFRP require a long curing time of epoxy plastics to make composites. To shorten the molding time, the thermoplastics of polycarbonate instead of epoxy resin was applied to make composite of carbon fiber reinforced thermoplastic polycarbonate plastics (CFRTP-PC). However, CFRTP-PC has lower impact strength than CFRP due to poor impregnation. In order to strengthen the impact strength of CFRTP-PC, electron beam irradiation (EBI) has been performed. The optimal dose (107.5 - 129 kGy) of EBI at 250 kV improves the impact value.

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This study explores the impact of leaks on the fraction of inspired oxygen (FiO₂) during noninvasive positive pressure ventilation (NPPV) with home oxygen therapy (HOT) in patients with chronic obstructive pulmonary disease (COPD). The study uses liquid oxygen instead of an oxygen concentrator typically used in HOT, and compares the results to a previous study. The study finds that while FiO₂ values decrease with increasing leaks, there is no statistically significant difference in the overall comparison, and there are no statistically significant differences for certain ventilation volumes. The study suggests that liquid oxygen may be more adequate for severely ill COPD patients, and provides meaningful results for target PaO₂ values in clinical practice. Limitations include the study being a basic experiment with simulated lungs, and further data collection is needed to compare the effects of oxygen concentrators on FiO₂ values.

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Measurement of volatile organic compounds (VOCs) contained in exhaled air and skin gas would be effective for the noninvasive assessment of metabolism and disease screening. Furthermore, simultaneous measurement of multiple VOCs that were generated at the same metabolic pathway is important for understanding metabolic functions, e.g., evaluation of alcohol metabolism possible by measuring ethanol (EtOH) and acetaldehyde (AcH). Here we report a parallel gas-imaging system of breath EtOH and AcH using the oxidation and reduction reactions of nicotinamide adenine dinucleotide (NADH)-dependent alcohol dehydrogenase (ADH). This system allowed gas-imaging of two VOCs by using a high-sensitivity camera to capture a fluorescence of NADH (excitation:340 nm, fluorescence: 490 nm), which increased by the oxidation of EtOH and decreased by the reduction of AcH catalyzed by the ADH in the enzyme immobilized meshes placed parallel in front of the camera. In addition, the system was possible to quantify the EtOH and AcH in exhaled air after alcohol consumption based on the image analysis technique.

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